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Insects' ethology is an important factor when it is desired to carry out pest management. This knowledge makes it possible to manipulate behavioral activities, repel, or attract insects according to needs and interests. The maize weevil Sitophilus zeamais (Mots., 1855) (Coleoptera: Curculionidae), one of the main stored grain pests, has been the target of studies of behavioral changes studies through natural substances due to its resistance to different insecticidal classes. Thus, this study aimed to evaluate the effect of sublethal concentrations of neem extract and copaiba oil on the locomotor behavior of S. zeamais. The behavioral characteristic considered were walking activity, the frequency of contact of insects with the treated grain mass, and the time spent for this behavior. The walking activity of the S. zeamais increased with exposure to Neem extract and Copaiba oil. In general, the Neem extract and Copaiba oil-induced more contact with grain mass than the control, suggesting an attractive effect on the insect, however more significant for the Neem oil. The insect's behavior was altered, presenting a specific path due to Copaiba oil and Neem extract stimuli. These results indicate that Copaiba oil and Neem extract can be a potential alternative for controlling S. zeamais on stored products since changes in this pests' behavior can reduce qualitative and quantitative grain damage. Thus, the development of products based on Copaiba oil and Neem extract may be helpful for storage pest management. Resumo A etologia dos insetos é um fator importante quando se deseja relizar manejo de pragas. Através deste conhecimento, é possível manipular atividades comportamentais, repelir, ou atrair os insetos de acordo com as necessidades e interesses. O gorgulho do milho Sitophilus zeamais (Mots., 1855) (Coleoptera: Curculionidae), uma das principais pragas de grãos armazenados tem sido alvo de estudos de alterações comportamentais através de substâncias naturais devido à sua resistência a diferentes classes de insecticidas. Assim, este estudo teve como objetivo avaliar o efeito de concentrações subletais de extrato de neem e do óleo de copaíba sobre o comportamento de movimentação de S. zeamais. As características comportamentais consideradas foram: a atividade de caminhamento, a frequência do contato dos insetos com a massa de grãos tratada, e o tempo gasto para realização destes comportamentos. A atividade de caminhamento do S. zeamais aumentou quando os insetos foram expostos ao extrato de Neem e ao óleo de copaíba. Em geral, o extrato de Neem e o óleo de Copaíba induziram mais contato com a massa de grãos do que o controle, sugerindo um efeito atrativo sobre o inseto, contudo este efeito foi mais significativo para o óleo de Neem. O comportamento do inseto foi alterado, apresentando um caminhamento específico devido aos estímulos do óleo de copaíba e do extrato de Neem. Estes resultados indicam que o óleo de copaíba e o extrato de Neem podem ser alternativas potenciais para o controle do S. zeamais em produtos armazenados, uma vez que alterações no comportamento desta praga podem reduzir os danos qualitativos e quantitativos nos grãos. Assim, o desenvolvimento de produtos baseados no óleo de copaíba e no extrato de Neem pode ser útil para o manejo de pragas de armazenamento.

Control failure of pests and selectivity of insecticides to beneficial arthropods are key data for the implementation of Integrated Pest Management (IPM) programs. Therefore, the aim of this study was to assess the control failure likelihood of Plutella xylostella and the physiological selectivity active ingredients to parasitoid Oomyzus sokolowskii (Hymenoptera: Eulophidae) and to predators Polybia scutellaris (Hymenoptera: Vespidae) and Lasiochilus sp. (Hemiptera: Anthocoridae). In bioassays, P. xylostella larvae and O. sokolowskii, P. scutellaris and Lasiochilus sp. adults were used. Concentration-mortality curves of six insecticides for P. xylostella were established. These curves were used to estimate the mortality of P. xylostella at the recommended concentration, in order to check a control failure of insecticides to this pest. Furthermore, the lethal concentration for 90% of populations (LC90) and the half of LC90 were used in bioassays with the natural enemies to determine the selectivity of these insects to insecticides. All tested insecticides showed control failure to P. xylostella, indicated by high LC90 and low estimated mortalities (less than 80%). The cartap insecticide was selective in half of LC90 to Lasiochilus sp. and moderately selective in LC90 and the half of LC90, to Lasiochilus sp. and P. scutellaris, respectively. Deltamethrin was moderately selective in the half of LC90 to predator Lasiochilus sp. Cartap, carbaryl, and deltamethrin reduced the mortality of Lasiochilus sp. in the half LC90. The results also showed that the insecticides methamidophos, carbaryl, parathion methyl and permethrin were not selective to any of the tested natural enemies. The role of insecticides in IPM systems of Brassica crops is discussed based on their control failures to P. xylostella and selectivity to their natural enemies.

At the global level, Sorghum bicolor (L.), is one of the most important crops, which ranks fifth among all cereals. It is cultivated in Africa, Asia, Oceania and the Americas, where it serves as a source of food and feed for humans and animals, respectively. However, production is constrained by several factors including pests and diseases. Among the pests that are known to attack Sorghum, Schizaphis graminum (Rondani), commonly called the green cereal aphid, is the most destructive pest of sorghum. S. graminum damage to sorghum is worsen by water deficit which favors its occurrence. Limited information on the spatial distribution of the pest and its natural enemies impedes the development of ecologically friendly management strategies. Therefore, the objective of this research was to determine the spatiotemporal distribution of S. graminum and its natural enemy Coccinella septempunctata (L.) during the vegetative and reproductive stage of the crop using geostatistical analysis. The spatiotemporal distribution of S. graminum was influenced by Sorghum development stage, surrounding landscape, and presence of its main predator C. septempunctata. Moreover, the abundance of C. septempunctata was influenced by the density of S. graminum. The findings from this study are required for developing sustainable pest management strategies against S. graminum. Resumo Em uma escala global o Sorghum bicolor (L.) é uma das culturas mais importantes, ocupando o quinto lugar entre todos os cereais. É cultivada na África, Ásia, Oceania e Américas, onde serve como fonte de alimento e ração para humanos e animais, respectivamente. No entanto, a produção é limitada por vários fatores, incluindo pragas e doenças. Entre as pragas que atacam o sorgo, Schizaphis graminum (Rondani), comumente chamado de pulgão verde dos cereais, é a praga mais destrutiva do sorgo. O dano de S. graminum ao sorgo é agravado pelo déficit hídrico que favorece sua ocorrência. Informações limitadas sobre a distribuição espacial da praga e seus inimigos naturais impedem o desenvolvimento de estratégias de manejo ecologicamente corretas. Portanto, o objetivo desta pesquisa foi determinar a distribuição espaço-temporal de S. graminum e seu inimigo natural Coccinella septempunctata (L.) durante a fase vegetativa e reprodutiva da cultura por meio de análise geoestatística. A distribuição espaço-temporal de S. graminum foi influenciada pelo estágio de desenvolvimento do sorgo, paisagem circundante e presença de seu principal predador C. septempunctata. Além disso, a abundância de C. septempunctata foi influenciada pela densidade de S. graminum. Os resultados deste estudo são necessários para o desenvolvimento de estratégias sustentáveis de manejo de pragas contra S. graminum.

The small tomato borer, Neoleucinodes elegantalis (Guenee) (Lepidoptera: Crambidae), is a significant pest of tomato crops in Central and South America, where its occurrence and abundance is dependent on environmental factors. The aim of this study was to determine the effects of climate variables on the abundance of N. elegantalis in open-field tomato cultivation. The population density of N. elegantalis was sampled weekly after tomato fruits reached a diameter ≥0.5 cm until the final harvest, over 15 commercial tomato fields. Egg abundance and mortality, larval abundance and mortality, and pupae abundance was determined within each sample. Rain, photoperiod, wind speed, temperature, and relative humidity was monitored daily. The highest densities of N. elegantalis eggs, larvae, and pupae occurred between March and July. After July, N. elegantalis density was drastically reduced. Path analysis revealed that temperature, rainfall, and photoperiod had a significant and direct effect on N. elegantalis egg abundance, which indirectly affected larval and pupal densities. The path coefficient indicated a negative correlation between the number of N. elegantalis eggs and the photoperiod, while air temperature and rainfall had a positive effect on theses densities. This study improves our understanding of how climate influences N. elegantalis population dynamics. This information will assist in the development of more sustainable pest-management programs for tomato fields, allowing farmers to monitor and adopt control methods when populations rise.

The red spider mite Tetranychus evansi can cause up to 90% yield losses to tomato crops. Mechanisms and causes of plant resistance to this pest could contribute to improved planning of plant breeding programs that prevent damage by this pest. It is known that the morphology and chemical compounds present in tomato plants are important to Tetranychus spp. success. This study aims at evaluating the resistance of 84 arbitrarily chosen tomato accessions obtained from the Horticulture Germplasm of the Universidade Federal de Viçosa (HGB-UFV), Minas Gerais State, Brazil to T. evansi. We evaluated the number of spider mites per leaf disk, number of trichomes/mm2, and the concentration of hydrocarbons of leaf disk. A significant difference in the number of T. evansi adults/leaf disk was found among accessions. The resistance mechanism of the HGB-UFV accessions was determined to be antixenosis. Accessions 2004, 2098, 2121, and 2100 had higher trichome density and the lowest adult T. evansi per tomato leaf disk. For this reason, these accessions should be chosen as sources of resistance in plant breeding programs. The hydrocarbons C 11 , C 13 , and C 22 had a negative correlation with T. evansi adults per leaf disk.

Understanding how the biotic and abiotic factors influence pest-population dynamics is important to implement sound pest management strategies in biological control and integrated pest management (IPM) programmes. Coccus viridis (Green) is an important indirect pest of coffee plants, but very little has been done to understand the factors that contribute most for its biological control in the field. In the present study, we examined the critical life stage and the key factors associated with the mortality of C. viridis in coffee plantations in Brazil by conducting field-based life table studies. Predators, parasitoids, fungi, infested leaf abscission and rainfall were collectively responsible for a total C. viridis mortality of 96.08%. Predation by coccinellids was the key factor governing the mortality of C. viridis. The parasitism of early instars by parasitoids was the second most important factor contributing to C. viridis mortality. Unlike the parasitoids, the fungus Lecanicillium lecanii caused mort...

Coffee (Coffea spp.) alkaloids (caffeine and related methylxanthines) and phenolics (caffeic and chlorogenic acids) have recognized pestistatic/pesticidal activity and mediate insect-plant interactions. The present investigation assessed the resistance of 12 coffee genotypes to the leaf miner Leucoptera (= Perileucoptera) coffeella (Guerin-Meneville & Perrottet) (Lepidoptera: Lyonetiidae) and correlated such results with the leaf content of coffee alkaloids and phenolics that probably play a role in the interaction between coffee and this leaf miner. The levels of chlorogenic and caffeic acid, caffeine, and related methylxanthines were measured and quantified in leaf extracts of these genotypes before and 7 d after their infestation by the leaf miner. Some coffee genotypes (Coffea canephora L. and Coffea racemosa Lour. and its hybrids with Coffea arabica L.) exhibited high pesticidal activity (100% mortality) toward the L. coffeella, indicating their antibiosis resistance. However, there was no correlation between this activity and the leaf levels of coffee alkaloids and phenolics. Curiously, infestation by L. coffeella leads to a nearly four-fold decline in the leaf levels of chlorogenic acid, which does not affect this pest species but may affect other generalist species. Indeed, chlorogenic acid sprayed on coffee leaves stimulated locomotory activity of the green scale Coccus viridis (Green) (Hemiptera: Coccidae), thus minimizing their feeding in contrast with the absence of this polyphenol. Therefore, reduction of chlorogenic acid levels in coffee leaves due to leaf miner infestation seems to also favor infestation by generalist insects, such as the green scale.

A conventional sampling plan for the leafhopper Empoasca kraemeri Ross & Moore (Auchenorrhyncha: Cicadellidae) in common beans (Phaseolus vulgaris L.) is presented based on samples from 51 commercial fields. The research encompassed three phases. The first phase had the objective of determining the most suitable leaf to be used as a precise and representative sampling unit. In the second phase of the project, the available sampling methods for E. kraemeri were compared, including the approach identified in the first phase. In the third phase, the theoretical frequency distribution of the sampling data was assessed and the number of samples necessary for the sampling plan was established. The best leaves to sample adult leafhoppers were the fourth and the fifth from the apex, while the best leaf for sampling nymphs was the fifth from the apex. The best sampling technique for nymphs and adults was the beating of the apical leaves against a plastic tray. The sampling data obtained with this technique were fit to a negative binomial distribution with common aggregation parameter for adults (K common = 1.04) and nymphs (K common = 0.47). This sampling plan required 16.8 and 31.2 min to be carried out at an expense of US$ 0.31 and US$ 0.54 for sampling adults and nymphs in a field, respectively.

The critical components and the key factors of yield losses in autumn–winter and spring–summer cucumber crops were determined and quantified in Vicosa county, State of Minas Gerais, Brazil, in areas cultivated with gynoecium hybrids of the groups Aodai (Sprint 440 II) and “Caipira” (Vlasstar). The data were used to build crop life tables. The overall losses in the autumn–winter and spring–summer cultivations were of 53.5 and 66.6 ton ha −1 , representing 76.3% and 59.2% of the overall crop yield potential. A critical component of yield loss was flower abortion in both cultivation periods. Fruit loss in the autumn–winter cultivation period was due to deficient pollination and production of non-marketable fruit size, and fruit damage caused by Diaphania spp. (Lepidoptera: Pyralidae), factors that also affected losses in the spring–summer cultivation period, followed by the physiological disturbance caused by nitrogen deficiency.

Este trabalho objetivou estudar a seletividade dos inseticidas carbaril, deltametrina, paratiom metílico, permetrina e triclorfom em favor do predador Doru luteipes (Scudder) (Dermaptera: Forficulidae) e do parasitóide Cotesia sp. (Hymenoptera: Braconidae), em relação ao controle do curuquerê Ascia monuste orseis (Godart) (Lepidoptera: Pieridae). Foram determinadas as CL90 para A. monuste orseis e estas foram utilizadas como doses discriminatórias para se avaliar o grau de seletividade dos inseticidas. Deltametrina e permetrina foram altamente seletivos em favor de D. luteipes. Deltametrina foi medianamente seletiva em favor de Cotesia sp. e a permetrina não apresentou seletividade em favor deste parasitóide. Triclorfom foi altamente seletivo em favor de ninfas de quarto estádio e adultos de D. luteipes e mediamente seletivo em favor de Cotesia sp. e de ninfas de primeiro estádio do predador. Carbaril foi medianamente seletivo em favor de Cotesia sp. mas não apresentou seletividade em favor de D. luteipes. Paratiom metílico não foi seletivo em favor de Cotesia sp. e D. luteipes. Adultos de D. luteipes foram menos sensíveis a deltametrina, permetrina e triclorfom do que adultos de Cotesia sp., sendo que o inverso ocorreu com o carbaril. Esses inimigos naturais apresentaram alta sensibilidade ao paratiom metílico. Ninfas de quarto estádio e adultos de D. luteipes foram mais sensíveis ao paratiom metílico e triclorfom que ninfas de primeiro estádio. Ninfas e adultos de D. luteipes apresentaram semelhante sensibilidade ao carbaril, deltametrina e permetrina. This work aimed to study the selectivity of the insecticides carbaryl, deltamethrin, methyl parathion, permethrin and trichlorfon in favor of the predator Doru luteipes (Scudder) (Dermaptera: Forficulidae) and of the parasitoid Cotesia sp. (Hymenoptera; Braconidae) in relation to the control of the kale leafworm Ascia monuste orseis (Godart) (Lepidoptera: Pieridae). LC90 were determined for A. monuste orseis, and these were used as discriminatory doses to evaluate the degree of selectivity of the insecticides. Deltamethrin and permethrin were highly selective in favor of D. luteipes. Deltamethrin was intermediate selectivity in favor of Cotesia sp., while permethrin was not selective in favor of this parasitoid. Trichlorfon was highly selective in favor of fourth instar nymphs and adults of D. luteipes, and it was intermediate selectivity in favor of Cotesia sp. and first instar nymphs of the predator. Carbaryl was intermediate selectivity in favor of Cotesia sp., but it did not show selectivity in favor of D. luteipes. Methyl parathion did not show selectivity in favor of D. luteipes and Cotesia sp. Adults of D. luteipes were less sensitive to deltamethrin, permethrin and trichlorfon than adults of Cotesia sp. and the inverse happened with carbaryl. Both natural enemies presented high sensibility to methyl parathion. Fourth instar nymphs of and adults of D. luteipes were more sensitive to methyl parathion and trichlorfon than first instar nymphs. Both nymphs and adults of D. luteipes presented similar sensibility to the carbaryl, deltamethrin and permethrin.

Several sampling plans have been developed for many insect pest species. However, few sampling plans have been based on attractant-baited traps. The coffee berry borer Hypothenemus hampei (Coleoptera: Curculionidae: Scolytinae) is a key coffee pest of worldwide importance whose sampling plans usually demand the harvest and inspection of up to 5,000 coffee berries per field, which is labor-intensive, costly, and ineffective. Therefore, this system constitutes a good model for the development of a more cost-effective sampling plan based on attractant-baited traps for capturing adult insects allowing the sustainable management of this pest species. The reported study was performed in 27 coffee fields using berry damage-assessment techniques and capture of adult borers applying attractant-baited traps made of PET-bottles (polyethylene terephthalate bottles). The relationship between trap capture and berry damage was significant allowing the use of the former to estimate coffee loss caused by the borer. The trap capture data from the coffee fields were adjusted to a negative binomial distribution suitable for establishing a single conventional sampling plan for all investigated fields. The required trap density varied from 14 to 355 traps/10 ha, depending on the precision error selected. The sampling plan developed using spatial interpolation (kriging and inverse weighted-distance methods) indicated that using 22 traps/10 ha for sampling of the coffee berry borer, costing US$ 303.24/10 ha and requiring 49.14 min/10 ha for the sampling procedure, was suitable and resulted in cheaper, faster, and more reliable estimates compared to present recommendations.

The objective of this work was to study the effect of plant canopy height on the resistance of the tomato species Lycopersicon hirsutum to the tomato leafminer Tuta absoluta. Determination of the levels of tridecan-2-one (2-TD) and undecan-2-one (2-UD) in L. hirsutum, as well as the leaf area, density and types of trichomes present in L. hirsutum and L. esculentum were made on apical, medium and basal parts of plant canopy. Correlation of these data were made with the following biological characteristics of T. absoluta: rates of oviposition and egg hatching; length of egg, larval and pupal stages; mortality of the larval and pupal stages; pupal weight; and sex ratio. Levels of 2-TD on leaves of L. hirsutum increased from bottom to top of canopy. Tuta absoluta had higher oviposition and egg hatching, as well as lower mortalities and smaller larval and pupal periods in L. esculentum than in L. hirsutum. Longer pupal period and greater number of small and large mines of T. absoluta were verified in the apical and medium parts of L. hirsutum plants. On the other hand, higher pupal mortality and longer larval periods were obtained in the apical and basal parts of the L. hirsutum plants. Larval mortality was higher in the basal part of those plants. In L. esculentum, leaves from the apical part of the plant promoted lower mortality, longer larval period and greater number of large mines of T. absoluta. However, a shorter pupal period was verified on leaves of the basal part. It appears that an increase in glandular trichome density in L. hirsutum leads to an increase in the levels of 2-TD, which, in turn slows down larval development.

It is important to understand how components of the agroecosystem interfere with the attack of a pest species and their seasonality in order to use these components in IPM programs. This study focused on the evaluation of the seasonality of natural control factors associated with the guava psyllid Triozoida limbata (Enderlein) in Brazil. Life-table data were collected from an experimental guava orchard during four periods that roughly represented four seasons. Natural mortality was monitored daily through the immature stages, and the relative importance of each natural mortality factor and its seasonality was determined. Significant statistical differences were observed in the mortality during the four periods (P T. limbata, including rainfall, physiological disturbance, the parasitoid Psyllaephagus sp. (Hymenoptera: Encyrtidae) and specific predators: syrphids, predatory wasps and other generalist predators. Depending on the location of nymphs (exposed or inside galls), the relative importance of the different natural mortality factors changed. The principal component analysis (PCA) showed some trends in the relationship of natural control agents and weather conditions. For example, the occurrence of predatory wasps was positively correlated with temperature and occurrence of winds; the occurrence of syrphids and Psyllaephagus sp. were negatively correlated with temperature and winds; and the occurrence of other generalist predators were negatively correlated with the occurrence of rainfall and photoperiod. The results showed the importance of natural mortality factors for the management of T. limbata and their changes through the different seasons which should be considered when implementing IPM programs in guava orchards.

Phytochemicals may modify the food quality, reduce a plant's palatability to insects, or defend against pests. This work aimed to study 1) relationships between the nitrogen and potassium levels given to plants in nutritive solutions and the foliar phytochemical concentrations, 2) the effect of nutrients and secondary compounds of Coffea arabica on the behavior of Coccus viridis, and 3) tolerance of C. arabica to losses. Deficient, normal, and excessive nitrogen and potassium fertilization treatments were used. Each treatment had two plants (one infested and one noninfested plant). The contents of phytochemicals in the infested plants' leaves and their dry matter of roots, stems, and leaves as well as the total contents in noninfested plants, were determined. The adults and nymphs of C. viridis were counted for 60 d in all treatments. It was verified that elevated nitrogen and potassium levels in the nutritional solutions led to increased of nymphs and adults of C. viridis to the coffee plants over time. Potassium and nitrogen had both direct and indirect effects on C. viridis. The direct effect was because of the increase of the nitrogen content in the leaves. The indirect effect instead was because of reductions in the caffeine and chlorogenic acid contents in the leaves. This is the first study to show relationship nutrient levels of coffee phytochemicals in response to herbivory by scale insects. Caffeine and chlorogenic acid applied on coffee leaves stimulated the locomotory activity of the green scale, thus reducing their feeding compared with untreated leaves. The elevation of caffeine and chlorogenic acid levels in coffee leaves affect this generalist insect by stimulating the locomotion of crawlers.

Coffee (Coffea spp.) alkaloids (caffeine and related methylxanthines) and phenolics (caffeic and chlorogenic acids) have recognized pestistatic/pesticidal activity and mediate insect-plant interactions. The present investigation assessed the resistance of 12 coffee genotypes to the leaf miner Leucoptera (= Perileucoptera) coffeella (Guérin-MénevillePerrottet) (Lepidoptera: Lyonetiidae) and correlated such results with the leaf content of coffee alkaloids and phenolics that probably play a role in the interaction between coffee and this leaf miner. The levels of chlorogenic and caffeic acid, caffeine, and related methylxanthines were measured and quantified in leaf extracts of these genotypes before and 7 d after their infestation by the leaf miner. Some coffee genotypes (Coffea canephora L. and Coffea racemosa Lour. and its hybrids with Coffea arabica L.) exhibited high pesticidal activity (100% mortality) toward the L. coffeella, indicating their antibiosis resistance. However, there was no correlation between this activity and the leaf levels of coffee alkaloids and phenolics. Curiously, infestation by L. coffeella leads to a nearly four-fold decline in the leaf levels of chlorogenic acid, which does not affect this pest species but may affect other generalist species. Indeed, chlorogenic acid sprayed on coffee leaves stimulated locomotory activity of the green scale Coccus viridis (Green) (Hemiptera: Coccidae), thus minimizing their feeding in contrast with the absence of this polyphenol. Therefore, reduction of chlorogenic acid levels in coffee leaves due to leaf miner infestation seems to also favor infestation by generalist insects, such as the green scale.

The population density of the coffee leaf miner Leucoptera coffeella (Gue ´- rin-Meneville & Perrottet) (Lep., Lyonetiidae) can be estimated using pheromone traps in coffee fields as male capture reflects this pest dam- age based on previous correlational study. However, the spatial distribu- tion of pheromone traps and their density are necessary to optimize the sampling procedure with pheromone traps. Therefore, the objectives of the present study were to determine the pheromone trap density required per hectare to sample coffee leaf miner populations and to determine the spatial distribution of the males of this pest species. The males were sampled every 8 days in 12 consecutive evaluations. Taylor's power law and frequency distributions were used to recognize the distri- bution of the male capture data, which followed a negative binomial distribution. A common K was obtained, allowing the establishment of a single conventional sampling plan for the 12 fields investigated. The adjusted sampling plan requires eight traps in an area of 30 ha for a 25% precision error. Kriging-generated maps allowed the simulation of male captures for 8, 12 and 20 traps per 30 ha and the results were compared with those obtained with absolute sampling resulting in R 2 -values of 0.30, 0.57 and 0.60 respectively. The traps were able to identify the more highly infested areas within the field and are a precise and efficient tool for sampling populations of L. coffeella. J. Appl. Entomol.

Pest monitoring with pheromone traps is affected mainly by factors such as trap placement and pest biology. The intertrap distance can affect the capture due to competition among traps that are placed at short distances. We studied the interference among pheromone traps used to monitor males of the coffee leaf miner, Leucoptera coffeella (Guerin-Meneville) (Lepidoptera: Lyonetiidae), with traps placed at various distances. Using geostatistical analysis, we determined at what distance captures were independent from other traps. Traps were placed in groups of 12 with distances among traps per group either 2, 5, 10, 15, or 30 m. Traps were checked for males every 4 days during 16 days. We found interference between traps when intertrap distances were shorter than 10 m. The range and magnitude of spatial dependence varied considerably among each sampling date and wind direction. For directions of 45° and 135°, the traps should be placed 110 and 177 m apart, respectively, to obtain spatially independent counts and therefore representative samplings for assessing the insect population in the area. These results have implications for developing sampling plans for managing L. coffeella with pheromone traps; the spatial analysis indicated that a trap density of one pheromone trap for every 3.5-4 ha would be adequate for the monitoring of the coffee leaf miner.

Individuals of two populations of Trichogramma maxacalii (Hymenoptera: Trichogrammatidae) were collected from eggs of Euselasia apisaon (Lepidoptera: Riodinidae), a lepidopteran defoliator of Eucalyptus, in plantations in the states of São Paulo and Minas Gerais, Brazil. This study investigated the sex ratio, number of parasitoids per egg, and longevity of individuals of these two populations of T. maxacalii, when this parasitoid was reared receiving eggs of the factitious host Anagasta kuehniella (Lepidoptera: Pyralidae) in different periods after emergence, and with or without honey. Sex ratio of T. maxacalii varied from 0.44 to 0.60, and was affected by the interaction between populations, availability of food (honey), and length of time in which the parasitoid stayed without host eggs after their emergence. The population of T. maxacalii collected in São Paulo produced a larger number of individuals per egg of the host A. kuehniella and lived longer when fed. Duas populações de Trichogramma maxacalii (Hymenoptera: Trichogrammatidae) foram coletadas de ovos de Euselasia apisaon (Lepidoptera: Riodinidae), um lepidóptero desfolhador de Eucalyptus, em plantios nos Estados de São Paulo e Minas Gerais, Brasil. Esta pesquisa avaliou a razão sexual, o número de parasitóides por ovo e a longevidade dos indivíduos dessas duas populações de T. maxacalii, quando esse parasitóide foi criado recebendo ovos do hospedeiro alternativo Anagasta kuehniella (Lepidoptera: Pyralidae) em diferentes períodos após a emergência e recebendo ou não mel como alimento. A razão sexual de T. maxacalii variou de 0,44 a 0,60 e foi afetada pela interação entre população, disponibilidade de alimento (mel) e tempo que o parasitóide ficou sem receber ovos do hospedeiro. A população de T. maxacalii coletada em São Paulo produziu maior número de indivíduos por ovo de A. kuehniella e teve maior longevidade quando alimentada.

Increasing rates of insecticide use against the coffee leaf minerLeucoptera coffeella(Guérin-Méneville) and field reports on insecticide resistance led to an investigation of the possible occurrence of resistance of this species to some of the oldest insecticides used against it in Brazil: chlorpyrifos, disulfoton, ethion and methyl parathion. Insect populations were collected from ten sites in the state of Minas Gerais, Brazil and these populations were subjected to discriminating concentrations established from insecticide LC99s estimated for a susceptible standard population. Eight of the field-collected populations showed resistance to disulfoton, five showed resistance to ethion, four showed resistance to methyl parathion, and one showed resistance to chlorpyrifos. The frequency of resistant individuals in each population ranged from 10 to 93% for disulfoton, 53 to 75% for ethion, 23 to 76% for methyl parathion, and the frequency of resistant individuals in the chlorpyrifos resistant population was 35%. A higher frequency of individuals resistant to chlorpyrifos, disulfoton and ethion was associated with greater use of insecticides, especially other organophosphates. This finding suggests that cross-selection, mainly between organophosphates, played a major role in the evolution of insecticide resistance in Brazilian populations ofL. coffeella. Results from insecticide bioassays with synergists (diethyl maleate, piperonyl butoxide and triphenyl phosphate) suggested that cytochrome P450-dependent monooxygenases may play a major role in resistance with minor involvement of esterases and glutathioneS-transferases.

Estudo-se em laboratório a seletividade dos inseticidas carbaril, deltametrina, fenitrotiom, fentiom, malatiom, nalede, paratiom metílico e triclorfom aos predadores Protonectarina sylveirae (Saussure), Polistes versicolor versicolor (Olivier) e Protopolybia exigua (Saussure) (Hymenoptera: Vespidae) em concentrações que correspondem a 50% (subdose) e 100% (dose) da recomendação para o controle de Grapholita molesta (Busch) (Lepidoptera: Olethreutidae) na cultura do pêssego. Nas doses recomendadas, para controle de G. molesta, os inseticidas fenitrotiom, fentiom, paratiom metílico, nalede e triclorfom não apresentaram seletividade às três espécies de Vespidae, causando 100% de mortalidade a estas, com exceção do triclorfom que matou 96,9% de P. sylveirae. Carbaril e malatiom foram seletivos em favor de P. versicolor versicolor (18,6 e 6,7% de mortalidade, respectivamente), e deltametrina em favor de P. versicolor versicolor (3,7% de mortalidade) e P. exigua (11,9% de mortalidade). P. sylveirae foi mais suscetível a deltametrina que P. exigua e P. versicolor versicolor. Já P. versicolor versicolor foi mais tolerante a malatiom e carbaril que P. sylveirae e P. exigua. Deltametrina, malatiom e nalede causaram menor mortalidade em P. sylveirae quando aplicados em subdose, sendo que o mesmo ocorreu com carbaril e malatiom para P. exigua. The selectivity of the insecticides carbaryl, deltamethrin, fenitrothion, fenthion, malathion, naled, methyl parathion and trichlorfon to the predators Protonectarina sylveirae (Saussure), Polistes versicolor versicolor (Olivier) and Protopolybia exigua (Saussure) was studied in laboratory using 50 and 100% of the recommended dose for the control of Grapholita molesta (Busch) (Lepidoptera: Olethreutidae) in peach orchards. The insecticides fenitrothion, fenthion, methyl parathion, naled, and trichlorfon showed no selectivity in favour of the wasps at the full recommended dose, all of them causing 100% mortality among the predators except for trichlorfon which caused 96.9% mortality to P. sylveirae. Carbaryl and malathion were selective in favour of P. versicolor versicolor (18.6 and 6.7% mortality, respectively), and deltamethrin was selective in favour of P. versicolor versicolor (3.6% mortality) and P. exigua (11.8% mortality). P. sylveirae was more susceptible to deltamethrin than P. exigua and P. versicolor versicolor. P. versicolor versicolor was more tolerant to malathion and carbaryl than P. sylveirae and P. exigua. Deltamethrin, malathion and naled were less lethal to P. sylveirae when applied at the lower dose; while the same happened to carbaryl and malathion for P. exigua.

The effect of feeding on Eucalyptus leaves of Tynacantha marginata (Heteroptera: Pentatomidae) was studied in Brazil. The use of this plant as a complementary food source for the predatory bug increased its oviposition period, generation time, and net reproductive rate. Eucalyptus leaves apparently had no influence on the survival and development of T. marginata.

The reproductive parameters of Telenomus podisi, Trissolcus brochymenae (Hymenoptera: Scelionidae) and Ooencyrtus sp. (Hymenoptera: Encyrtidae) were studied for three generations on their natural host Podisus nigrispinus (Dallas, 1851) (Hemiptera: Pentatomidae). A parasitism rate of 10 eggs/day/species was used under laboratory conditions of 27 +/- 1 degrees C, 60 +/- 10% RH and 14 h of photophase. No significant differences were detected between generations in terms of net reproductive rate (Ro), intrinsic rate of natural increase (rm), generation time (T) and the effect of doubling time on population increase (DT). However, T. podisi and T. brochymenae had significantly higher Ro and rm values, and lower T and DT values, with rm 1.59 and 1.50 times higher than Ooencyrtus sp., respectively. In addition the former species also had shorter egg-adult period, greater longevity of females and reproduction period than the other species. These results confirm the greater reproductive potential of T. podisi and T. brochymenae, which are commonly found parasitizing P. nigrispinus.

Mango (Mangifera indica L.) is an economically important fruit crop in many tropical and subtropical regions. Recently, the wilt disease caused by Ceratocystis fimbriata has limited mango production in Brazil and other countries (3). There are reports that Hypocryphalus mangifera (Coleoptera: Curculionidae) is a vector of Ceratocystis spp. and that other beetles, such as Xyleborus affinis (Coleoptera: Curculionidae), may attack mango trees and excavate gallery burrows, thereby producing sawdust (1,3). In March 2011, X. affinis was found colonizing diseased mango trees located in Itaperuna, Rio de Janeiro State (21°12′23″ S, 41°53′23″ W). Therefore, we aimed to evaluate whether both the beetle and the sawdust produced in colonized trees would be associated with C. fimbriata. In March 2011, three isolates of C. fimbriata were collected: CF01 in sawdust from ‘Espada’ trees with wilt symptoms (yellowish to dried leaves, dried stems, and gum exudation from the stem) in Itaperuna; CF02 from X. affinis colonizing wilted trees in Itaperuna; and CF03 from wilted ‘Palmer’ trees in Frutal, Minas Gerais State (20°1′11″ S, 48°55′10″ W). To obtain the isolates, fragments of sawdust, beetles, and mango stem were set between carrot disks and incubated in a wet chamber at 25°C with 12 h of light (4). After 10 days, the ascospores produced in perithecia in the carrot tissue were directly transferred to potato dextrose agar (PDA) in 9-cm petri dishes and incubated at 25°C with 12 h of light. After 10 days, 1-cm mycelial disks were taken from the borders of actively growing colonies. In each of 20 seedlings of 8-month-old ‘Espada,’ growing in 18 × 25 cm plastic pots with a soil-sand-cow manure mixture (3:1:1, v/v), a 1-cm diameter wound in the stem was made with a cork borer (20 cm above the soil surface). A mycelial disk was placed in each wound (a plain PDA disk was placed in control plants). After inoculation, a wet cotton plug was placed on the wound, which was then wrapped with Parafilm. Five plants were inoculated in each treatment. The seedlings were checked weekly for up to 56 days after inoculation. All three isolates were pathogenic, causing typical disease symptoms on the plants, beginning 7 days after inoculation: gum exudation (60, 60, and 0%); and yellowish and wilt (80, 100, and 80%). The % values are for isolates CF01, CF02, and CF03, respectively. No disease symptoms were observed in the control seedlings. After reisolating, the three isolates were confirmed as being C. fimbriata: perithecia (110 to 250 μm wide, 120 to 250 μm tall), base dark, globose, and long dark necks (440 to 770 μm long, 28 to 40 μm wide); ascospores hyaline, one-celled, galeate (5.0 to 7.5 μm long, 3.5 to 5.0 μm wide), exuded in sticky and cream colored mass at the apex of the perithecium neck (2). To our knowledge, this is the first report of an association between C. fimbriata and both X. affinis and the sawdust produced during beetle colonization. Therefore, both the beetle and the sawdust are potential dispersal agents of C. fimbriata in mango orchards. This finding is epidemiologically important, and the disease spread related to both sawdust and beetle is being followed in the field. References: (1) A. O. Al Adawi et al. Eur. J. Plant. Pathol. 135:243, 2013. (2) C. J. B. Engelbrecht and T. C. Harrington. Mycologia 97:57, 2005. (3) A. Masood et al. Pakistan J. Zool. 44:1545, 2012. (4) W. J. Moller and J. E. De Vay. Phytopathology 58:123, 1968.